The relationship between faith and wealth

As you can see in this chart, Sweden is a wealthy country and we do not find religion to be important at all (for example, apart from funerals I have not visited a religious ceremony in Sweden for as long as I can remember). The general pattern this chart reveals is that the greater the average living standard the inhabitants in a country have the more secularized they tend to be. There are of course exceptions, such as communist and some ex-communist countries. They are usually poor but they put less faith into divine matters than countries in the upper left cluster. The other major exception is the US. It is a wealthy nation but here 2/3 of the population still believes in holy matters. The difference between Sweden and the US is huge when it comes to this part (which is interesting considering how affected we have been by the US in other matters such as music, movies, TV, etc.). You will never hear the Swedish prime minister say “God Bless Sweden” (never mind that we have a cross in our flag). Intelligent design is hardly a problem here. The 2012 circus is also way stronger in the US than over here. It should not come as a surprise considering the strong religious and new age currents within that phenomenon. Maybe my hostility against too cosmological interpretations in archaeology is rooted in my own secularized past?